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A164031 a(n) = ((2+3*sqrt(2))*(5+sqrt(2))^n+(2-3*sqrt(2))*(5-sqrt(2))^n)/4. 2
1, 8, 57, 386, 2549, 16612, 107493, 692854, 4456201, 28626368, 183771057, 1179304106, 7566306749, 48539073052, 311365675293, 1997258072734, 12811170195601, 82174766283128, 527090748332457, 3380887858812626 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

COMMENTS

Binomial transform of A164072. Fifth binomial transform of A164073.

FORMULA

a(n) = 10*a(n-1)-23*a(n-2) for n > 1; a(0) = 1, a(1) = 8.

G.f.: (1-2*x)/(1-10*x+23*x^2).

PROG

(MAGMA) Z<x>:= PolynomialRing(Integers()); N<r>:=NumberField(x^2-2); S:=[ ((2+3*r)*(5+r)^n+(2-3*r)*(5-r)^n)/4: n in [0..19] ]; [ Integers()!S[j]: j in [1..#S] ]; [From Klaus Brockhaus (klaus-brockhaus(AT)t-online.de), Aug 09 2009]

CROSSREFS

Cf. A164072, A164073 (1, 3, 2, 6, 4, 12).

Sequence in context: A096711 A079926 A108666 * A023000 A097114 A022038

Adjacent sequences:  A164028 A164029 A164030 * A164032 A164033 A164034

KEYWORD

nonn

AUTHOR

Al Hakanson (hawkuu(AT)gmail.com), Aug 08 2009

EXTENSIONS

Edited and extended beyond a(5) by Klaus Brockhaus (klaus-brockhaus(AT)t-online.de), Aug 09 2009

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Last modified February 16 17:11 EST 2012. Contains 205938 sequences.